Financial Instruments Measured at Fair Value - Fair Value Hierarchy (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unrealized Gain on Securities		$ 378	$ 272	$ 2,220
Unrealized Loss on Securities					$ 6,971
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents		19,847		19,847		$ 22,883
Equity investments		43,071		43,071		38,045
Interest rate swaps- liability		(21,534)		(21,534)		(589)
Foreign exchange contracts - asset		30,533		30,533		4,163
Foreign exchange contracts - liability		(1,431)		(1,431)		(2,384)
Total Fair Value Assets And Liabilities Measured On Recurring Basis		70,486		70,486		62,118
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	[1]	19,847		19,847		22,883
Equity investments	[2]	43,071		43,071		38,045
Interest rate swaps- liability		0		0		0
Foreign exchange contracts - asset		0		0		0
Foreign exchange contracts - liability		0		0		0
Total Fair Value Assets And Liabilities Measured On Recurring Basis		62,918		62,918		60,928
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents		0		0		0
Equity investments		0		0		0
Interest rate swaps- liability		(21,534)		(21,534)		(589)
Foreign exchange contracts - asset		30,533		30,533		4,163
Foreign exchange contracts - liability		(1,431)		(1,431)		(2,384)
Total Fair Value Assets And Liabilities Measured On Recurring Basis		7,568		7,568		1,190
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents		0		0		0
Equity investments		0		0		0
Interest rate swaps- liability		0		0		0
Foreign exchange contracts - asset		0		0		0
Foreign exchange contracts - liability		0		0		0
Total Fair Value Assets And Liabilities Measured On Recurring Basis		$ 0		$ 0		$ 0
Marubun [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment Ownership Percentage		8.40%		8.40%

[1] Cash equivalents include highly liquid investments with an original maturity of less than three months.

[2] The company has an 8.4% equity ownership interest in Marubun Corporation and a portfolio of mutual funds with quoted market prices. The company recorded an unrealized gain of $378 and $2,220 for the third quarter and nine months ended September 28, 2019, respectively, on equity securities held at the end of the quarter. The company recorded an unrealized gain of $272 and an unrealized loss of $6,971 for the third quarter and nine months ended September 29, 2018, respectively, on equity securities held at the end of the quarter.